LEDs Stabilize Brightness For Portable-Display Backlighting

Osram Opto Semiconductors’ MicroSideled 3806 LEDs deliver consistent brightness to tablets, ultrabooks, and smartphones over their 15,000-hour lifetime. Even at the end of their rated life, the high-efficiency LEDs, available in white and blue, still provide 70% of their initial brightness (L70/B50). The standard white LED, with chip and converter, achieves 150-lm/W efficiency. The blue version offers 55% efficiency, measured as the external quantum efficiency, or EQE (the ratio of electrical power used to emitted optical power). It’s designed for display technology that uses quantum dots (special nanoparticles) as conversion material. The conversion technology involves a thin sheet with quantum dots in the backlight that’s illuminated by the blue LEDs. This leads to an extremely narrow-band emission spectrum that matches the backlighting unit’s color filters, minimizing light losses and creating more vibrant colors. The LEDs measure 3.8 by 1.0 by 0.6 mm. Thermal resistance is 66 (K/W).

OSRAM OPTO SEMICONDUCTORS